Discussions By Condition: Kidney conditions

Can the GFR test be wrong? A false low number?

My doctor's office just called to say my GFR is 55 and I need to come in for another test. Having no idea what that was, I googled it and am now TOTALLY FREAKED OUT. Third stage of incurable kidney disease!!! Please tell me this could be a mistake somehow. I don't smoke & rarely drink. My BP is normal, my cholesterol is awesome, my blood sugar is normal. I'm not diabetic. I'm not obese. I am 5'4 and 113 lbs. No history of kidney issues in my family. Could I be anemic? Could the number be from some psoas muscle issues I am currently seeing a PT about? I have no swelling or pain or any symptoms. I drink a lot of water. I am on the verge of a panic attack right now.